Photo-electric tube



g H. H. GEFFCKEN ET AL 1,924,275

PHOTO ELECTRIC TUBE Filed Dec. 6, 1928 Patented Aug. 1933 t v 1 i t UNITED. TA ES P TENT] OFFICE",

1,924,215 7 t V rno'ro-nnno'rarc TUBE Heinrich n. Geflckcn and Hans 1t. Richter, Leip- Y zig, Germany a 1 Application December 6, 192a. Serial No. 324,107 a Glaims. (01. 2501-275) v Our invention relates to photo-electric tubes quently the vaporized photo-electric material of the kind comprising a sealed bulb which may precipitates. only upon the surface of the inner be of glass, quartz or other suitable material, enwalls describing the recess. 2 and forms there a- I closing a film electrode. of light sensitive matefilm-1X9. In the accompanying drawing this film? rial '(such as potassium,sod.iumor the like) and. ha -e n d t d ya av l up n th containing a second electrode which collects the recess DQ OII- j electrons emitted by thefilm electrode when the In order to line the light Sensitive film by a latter is subjected to the influence of light. conductive y the recess y be coated In manufacturing such photo-electric tubes in y a layer of Silver the like b e t tub 1 theusual manner, the vaporized material is fed is exhausted. The film'eflight' Sensitive meteinto the tube, and, by cooling certain portions rial is finally formed y p s g a glow disof the tube and simultaneously heating other charge in hydrogen. The hydrogen is afterportions thereof, said material is precipitated 0n ward displaced and suitably replaced by argon,

the cooled portion, forming a conducting and helium or other inert gas. light sensitive film. This manner of manufactur- It is well known, that photo-electric tubes are 751;;

ing photo-electric tubes can only be performed by especially sensitive when the distance between skilled experts. The tube is very fragile and the photo-electric film and the anode member bursts easily during this process which requires is uniform at all points, providing a nearly homoheating of certain parts and simultaneous coolgeneous electric field between the anode electrode 0. of other parts. and thelight sensitive film. This principle can be 75.

Our invention relates to photo-electric tube fully utilized in the present invention due to the which do not require expert work and which may general provision of a recess. portion, and the be manufactured easily Without any danger of sensitiveness of our new photo-electric tube may" bursting. The essential feature of our novel be increased by surrounding the recess 2- by a 2 photo-eleotrio tube consists in the application of suitably shaped anode electrode placed in proper 3:

the light sensitive film material to a. recessed pordistance relative to the photo-electric film. Figtion in the wall of the tube. a I we 2 represents a photo-electric tube of this type. Our invention will best be'understood by de- A bag-like net or screen "10 connected to the tailed description with reference to the accomanode wire .31 is arranged closely to the interior r a s Single S t OfdraWing. p surface of the tube 11, surrounding the light F re 1 r p ts a d a mat vi w f sensitive film 19 applied to the inner wall of the i a photo-electric b in the State Of memlfaerecess in suitable uniform distance at all points. tllre; A Instead of usinga net, or screen 10, the interior Figure 2 represents 3 Similar phete-eleetric surface-of the bulb' 11 may be-coated with a film eftube, the anode electrode of which has a parof silver or the like, and this film'may be con- 96 tielller p and g nected to the anode wire 31 and utilized as anode. Figures 3 l' 4 represent 513601911 embedlments In order to avoid undesirable loss of light, this of our invention. anode film must be extremely transparent. It'

Referring W to Figure a recess 2 is p might be desirable in certain cases to use films m i in the tubebulb 1 e e y therein of a greater thickness and to divide such film on? as shown. Numeral 3 designates the anode elecby the use of wscraper device automatically. tmde- The Wire 4 Serves. as a terminal for the into adjoining sections or into a coiled line, thus I reception of current of the cathodic light sensiproviding betweenv the section's Smooth, trans I tive film. During manufacture, the tube 1 is parent portions i I 5; ..oonnected with the storage bulb 5 which contains The vSal-auger devices-Which y be'used f this e the light sensitive material (e. g., potassium, sopurpose are W611 known, for] example from e dium or the like). The recess portion 2 is closed process manufacturing Rowland grids, and I exteriorly by means of the stopper 6 which suptheir description is therefore omittei ports the tubes 7 and 8. The film of light sensi- In Figure 5 We have shown abortion of the tube I 5; tive material in the tube is produced as follows! to illustrate the application of a metallic film 1053 t t The t is exterierly heated d the vaporized to the walls of the'bulb, which may be used forphoto-electric material is driven from the storthe purpose of an anode in place of t bag-like age bulb 5 into the tube 1. A current of cold net as explained above. Like numerals 0 have air is simultaneously blown through tube 8 into been applied in this figure to designate parts I the interior of the recess portion 2. Consealready shown and discussed in connection with 1 Figure 2. The metallic film taking the place of net 10 in Figure 2 is designated in Figure 5 by reference numeral 10'.

Figure 3 represents another embodiment of our invention, showing a case in which the light sensitive film'has a spherical shape and surface. Such photo-electric tubes are especially adapted for measuring the total lighting of a point.

Figure 4 represents another embodiment of our invention, showing a photo-electric tube in which the light sensitive film has a cross section of ring formation. Photo-electric tubes of this kind are particularly adapted for the use in connec-,

tion with the radio transmission of'opaque pictures.

In View of the detailed description furnished in connection with Figures 1 and 2, it is believed that the two embodiments shown in Figures 3 and 4 can be readily understood without additional detailed description. I

It is understood that various changes and modifications may be made in the structural details and in the arrangement of parts disclosed in this case without departing from the spirit 25? of the invention, and We desire to have it under- 'velope, a recess in said envelope extending therein, alight sensitive cathode film applied only to the surface of said recess within said envelope, and a metallic anode net applied to the inner surface of said envelope opposite said recess carrying said cathode film. I

3. A photoelectric tube having a sealed elongated-envelope provided with a recess, a light sensitive cathode film applied to the surface of said recess within said envelope, and ,a'transparent anode film applied to the inner surface of said envelope opposite said recess. HEINRICH H. GEFFCKEN.

HANS'R. RICHTER. 

